Indian locomotive class YAM-1 explained

Indian YAM-1
Powertype:Electric
Serialnumber:Mitsubishi 1238–1255, 1378–1379
Builddate:1964–1966
Totalproduction:YAM-1: 20
Uicclass:B′B′
Locoweight:52t
Electricsystem:25 kV AC overhead
Collectionmethod:Two Faively AM-12 pantographs
Tractionmotors:Two ACEC/Alstom/Siemens MG1420 truck-mounted of 1250 V DC; 3.95:1 gear ratio
Transmission:One Mitsubishi 'Shell Sub', 1690-kVA, 25-tap transformer; four 510 A, 1250 V, type A268, Secheron excitron rectifiers
Maxspeed:800NaN0
Poweroutput:1300-1NaN-1
Tractiveeffort:191sigfig=3NaNsigfig=3
Locobrakes:Air
Trainbrakes:Vacuum
Operator:Indian RailwaysSouthern Railway zone
Operatorclass:YAM-1
Fleetnumbers:21904–21923
Nicknames:Pallava King, Vaigai Special
Locale:Southern Railway (India)
Withdrawndate:30 June 2004
Preservedunits:21909 at Regional Rail Museum, Chennai
21912 at CLW Loco Park
21922 at Tambaram EMU Shed

The Indian locomotive class YAM-1 is a class of metre gauge (Y), Alternating Current (A), mixed traffic (M) electric locomotives in India. Twenty were built in 1964–66 by a Japanese consortium led by Mitsubishi.

Background

When the Madras (now Chennai) to Tambaram line was electrified in 1931, the 1500 V DC system was originally used. As part of an extension of the electrification to Villupuram in 1965, the whole section was converted to the 25 kV AC system. Eighteen YAM-1 locomotives (later extended to 20), and YAU-1 4-car electric multiple units were built for service on the network.

Design

The YAM-1 locomotives were supplied in batches by Mitsubishi in 1964–66 (four in 1964, 14 in 1965 and two in 1966). They were jointly built by Mitsubishi, Toshiba and Hitachi, as shown by their builders' plates. They are of the B-B configuration, with two monomotor bogies, each with one bogie-mounted DC traction motor; the two traction motors were permanently coupled in parallel. They had an Oerlikon compressor and exhauster for the locomotive's air brakes and the train's vacuum brakes, and Arno rotatory converters. They were equipped with two Faively AM-12 pantographs.[1]

Service

They were not very powerful—they had a power output of 1.3-1NaN-1, a starting tractive effort of 191sigfig=3NaNsigfig=3, a maximum speed of 800NaN0, and a weight of 52t. They were given the fleet numbers 21904–21923.[2]

They were used on the electrified metre gauge lines of the Southern Railway zone of Indian Railways, usually in the Chennai area. With the conversion of the main lines to (broad) gauge, they were relegated to departmental service, although fifty-wagon goods trains were occasionally handled.

In their latter days, all 20 locomotives were allocated to Tambaram Electric Shed. The last use of a YAM-1 was on 30 June 2004, not long after the last EMU service on Chennai network reached Tambaram.

One unit has been preserved at Chittaranjan Locomotive Works.[3]

Locomotive shed

See also

External links

Notes and References

  1. Web site: Electric Locomotive Classes – AC . Indian Railways Fan Club . 2014-03-16.
  2. Web site: Diesel and Electric Locomotive Specifications . Indian Railways Fan Club . 2014-03-16.
  3. Web site: Roychoudhury . Samit . YAM-1 #21912 now preserved at the Loco Park at Chittaranjan Locomotive Works, WB . IRFCA.org . 4 June 2023.